package com.hmdp.utils;

import javafx.scene.input.DataFormat;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;
import java.util.Date;

//优惠券自增id
@Component
public class RedisIdWorker {

    private static final long BEGIN_TIMESTAMP=1640995200L;

    private static final int COUNT_BITS=32;
    @Resource
    private StringRedisTemplate stringRedisTemplate;
    public long nextId(String keyPrefix){
        //1.生成时间戳
        LocalDateTime now = LocalDateTime.now();
        //获取当前秒数
        long currentTime = now.toEpochSecond(ZoneOffset.UTC);
        //减去秒数，获取时间戳
        long timestamp=currentTime-BEGIN_TIMESTAMP;
        //2.生成序列号
        //2.1获取当前时间精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        //2.2自增长
        Long count = stringRedisTemplate.opsForValue().increment("icr" + keyPrefix + ":" + date);

        //3.拼接并返回 位运算
        return timestamp<<COUNT_BITS | count;
    }




}
